Soft crucible lowering down process for growing lithium fluoroaluminate crystals


Application Number: 00109223
Application Date: 2000.06.15
Publication Number: 1330172
Publication Date: 2002.01.09
Priority Information:
International: C30B15/00
Applicant(s) Name: Inst of Artificla Crystals, National Architectural Material Industry Bureau
Address:
Inventor(s) Name: Huang Chaoen;Cheng Lisen;Fang Zhenyi
Patent Agency Code: 11029
Patent Agent: hao xiaofang
Abstract A soft crucible lowering down method for growing lithium fluoroaluminate crystals features its low-temp solid-phase fluorination with NH4F as fluorinating agent and its soft crucible lowering down. Its technological steps include heating to 80-150 deg.C, low-temp pressure-reducing dewatering for 3-4 weeks, pressure-reducing fluorinating at about 300 deg.C for 24 hr, vacuum sintering at temp higher than 560 deg.C, and lowering down soft crucible made of Pt sheet with growth temp of 770-820 deg.c, temp gradient of 20-30 deg.C/cm, and growth speed of 5-10 mm/day.